Compressor



.June 7, 1927. 1,631,425

H. C. MARCUS ET AL COMPRES S OH- Filed March 1, 1925 4 Shasta-Sheet 1 i I: H Q N V W... V I I! v INVENTOR.

HENRY C. MARCUS W/A FEED FOUR/V555 wmwsss by A TTORNEYS.

June 7,1927. H. MARCUS ET AL COMPRESSOR Filed March 1, 192 3 4 sneets sneet 3 A I n 1% mmm [.1 T NM n :1 H R mg m9 3 E: g I I inwmi w. NM I I WHHH |l I i Kw R Q m n R mm R wk WITNESS June 7, 1927.

.. H. C. MARCUS ET AL COMPRESSOR Filed March 1, 1 23 4 Sheets-Sheet 4 jlijjiiji'g'ijqjt iii Fi l2 FIqIO L"- L- HEN/Q Y a. MA/ecus I I L W/L FRED FOUENESS WITNESS ATTORNEYS.

Patented June 7, 1927.

HENRY C. KABGUS, OF SAN FRANCISCO, AND WILFRED FO'UBNESS, OF OAKLAND, CALIFORNIA.

COMPRESSOR.

Application filed March 1, 1928. Serial No. 6%,023.

The invention relates to gas compressors and particularly to the type used in small refrigerating machines of the compression type.

.l Home refrigeratingv devices are, in genera], cumbersome and complicated, and require a comparatively large compressor unit. The compressors are usually motor driven and have a relatively low speed as compared with that of the motor, requiring the use of reduction gears. which increase the friction factor in the device as well as render it noisy. The use of a motor of high starting torque is necessary to overcome the inertia of the pistons when starting the compressor. The cost of this type of motor is about double that of the ordinary induction type, and its life is shorter. Also, a motor having the necessary horsepower to operate a refrigerating machine with this type of compressor, has a current consumption'out of proportion to the capacitv of the machine.

An object of the invention is to provide a high speed compressor adapted for direct connection to a motor. and embodving valves operable at a speed hitherto found impracticable.

Another object of the invention isto provide a high speed compressor having a low friction factor, requiring a relatively low horsepower electric motor for operation and so constructed that the need for a motor with a high starting torque is eliminated.

Another object of the invention is to provide 2r compressor with the lubricating oil under the discharge pressure of the compressor, so that the lubrication is positive and continuous.

Another object of the invention is to provide a small compressor as an integral part of a refrigerating unit, that may be doubled or quadrupled in capacity without increasing the size of the unit. thus increasing the rating of the refrigerating unit in the same proportion.

The invention possesses other objects and features of advantzwe, some of which, with the foregoing. will be set forth in the fol lowing description of our invention. it to be understood that. we do not limit ourselves to the showing made by the said de scription, as we may adopt variant forms of our invention "within the scope of the claims.

Referring to the drawings: Fig. 1 is a perspective view of the refrigerating unit installed on a refrigerator. A portion of a side wall and the back of the refrigerator are broken away in order to show the complete unit. Fig. 2 is a perspective view of 60 the compressor on its flanged mounting with the cover plate removed. Fig; 3 is a horiing the slot in the gasket, leading from the suction portto the main shaft. Fig. 8 is a vertical cross-section thru the compressor on the line 8-8, Fig. 2. The compressor is shown mounted in the discharge chamber of the apparatus. Fig. 9 is a diagrammatic I tion thru the cylinder block of the coir'rpressor in its preferred form with four cylin ders. Fig. 10 is a plan view of the cylinder block shown in Fig. 9. Fig. 11 is a diagram-v matic sectionthru the cylinder block of the compressor showing a modified arrangement giving eight cylinders and doubling the capacity of the compressor. Fig. 12 is a plan view of the cylinder block shown in Fig. 11. Fig. 13 is a plan view of two cylinder blocks similar to the one shown in Fig. 9, e0 placed together, showing another modified form having eight cylinders. Fig. 14 is a. plan view of two cylinder blocks, similar to the one shown in Fig. 11, placed together. showing a modified form giving sixteen cylinders and quadrupling the capacity of the compressor. Fi 15 is a diagrammatic section thru a m ified form of cylinder blockshowing an arrangement having eight cylinders. Fig. 16 is a plan View of the Ni cylinder block shown in Fig. 15. 17 is a diagrammatic section thru the cylinder block on the line 17-1Z, 16, showing the position oi the eccentrics. Fig. 18 is a plan view of two cylinder blocks, similar to the 1 one shown in Fig. 15, pieced together, showing another modified torn: having sixteen cylinders.

"valves of rapid and certain action, and with positive and continuous lubrication the high speed incident to direct connection to a motor becomes possible.

The compressor designated as a whole by the character 1 is directly driven by a motor 2 and is mounted on a cover plate 3, forming the closing head of a casing or recelver 4,

enclosing the chamber 6, into which the compressor discharges. Both receiver and motor are mounted upon a base-7. The compressed gas passes from the discharge chamber 6, thru the pipe 8 into the condenser 9 where the heat developed by the compression and condensation is absorbed by a stream of water, in the coils 11, entering the bottom of the condenser. The water passes from I the condenser coils thru the pipe 12, which is preferably wrapped around the casing 4 in the coils 13. From the condenser the liquid'sulphurdioxide is conducted thru the pipe 14 to the expansion valve 16 in the compartment 17, which is to be cooled and which forms the upper part of the refrigerator 18. There it is expanded into the coils 19, 20, and 21, which have a cooling surface sufficiently large tochill the compartment. The expanded gas is then conducted back to the com ressor thru the pipe 22 to begin a new cyc e. i A

The compressor, in its preferred 'form, comprises a cylinder block 23, preferablyin the form of a square ring, with a base plate 24 on one side, and a cover plate 26, on the opposite side. The three are secured together and to the receiver cover plate 3, by suitable screws 27 and studs 28. The space within the square ring forms the compressor supply chamber 29 into which the expanded gas discharges from the passage 31, which extends from the pipe 22 thru the receiver cover plate 3, and base plate 24, to terminate in an inlet port in one corner of the supply chamber.

Formed in the peripheral walls of the cylinder block are bores comprising four cylinders 33, v34, 36 and 37 radially disposed at 90 intervals about the axis of the drive shaft 38. Integrally formed on the drive shaft is an eccentric 39, with shoulders 40 and 41, Fig. 3, adapted for engagement with the interior surfaces of the cover plate 26 and the base plate 24, respectively, thereby keeping the eccentric centered inthe inlet chamber. Revolvably mounted about the eccentric is an eccentric block 42 having ex- .terior surfaces'disposed at 90 to each other.

53, adapted to work in cylinders 33 and 34,-.

respectlvely. Similarly, a piston rod 54, adjacent face 56 of the eccentric block 42, is adapted for horizontal movement, but is rigidly fixed against vertical movement.

This piston rod has interior vertical faces 57 and 58 adapted for engagement withfaces 59 and 61, respectively, of the eccentric block. Attached to the piston rod 54 by screws 62, are two oppositely disposed horizontal pistons 63 and 64 adapted to work in cylinders 36 and 37, respectively. Slot 66 in the piston rod 43 and slot 67 in the piston rod 54, allow a vertical and a horizontal movement respectively of each piston rod with reference to the drive shaft.

Rotating the shaft causes a circular movement of the eccentric block about the axis of the shaft, the exterior friction faces of the blockmaintaining parallelism, dueto their respective engagements with the piston rods, which, together with the connected pistons, are given a reciprocating motion. Each piston is a quarter ofits complete stroke in advance of the next following one, and each piston completes a full compression and suction stroke on the same single turn of the crank shaft.

Establishing communication between the inlet chamber 29 and each of the cylinders 33, 34, 36 and 37, are the suction ports 68. These suction ports are opened and. closed directly by thepistons, communication being established with each cylinder in. turn asthe piston completes its suction stroke. This insures a full charge of gas in the cylinder for each compressive stroke, the vacuum in the cylinder, as the piston nears the end of its suction stroke, causing a maximum amount of the gas from the inlet chamber, at substantially zero or atmos heric pressure, to be rapidly drawn into i318 cylinder. Since each cylinder has direct access to the relatively large inlet chamber, which isfillcd at all times with sulphur dioxide gas at substantially atmospheric pressure. a cushioning action results, thereby eliminating any tendency toward a wire drawing effect which would be present if each cylinder obtained its charge. thru separate leads, from a remote source of gas supply.

The end of each cylinder constitutes a discharge port, the bores extending entirely thru the cripheral wall of the cylinder block. he valves 69, seat directly on the exterior surfaces of the cylinder block over the open end of the bore, and comprise a thin circular plate or disk having a circumference sufiiciently greater than that of the cylinder to provide seating surface. The edge of the disk is provided with notches 71 to decrease the'b'earingama on the seat and therefore lessen any tendency of the valve to 'stick.' 'The notched edge also allows the compressed gas to pass the valve more rapidly when open. The valve is kept centered over the cylinder by the valve housing 72, rigidly secured to the cylinder block, and has a very slight movement which is limited under normal operating conditions by the stop 74. The valve contactingface of the sto is rounded to allow a greater latitude or movement of the edge of the valve in the event of.its sticking. A pin 77, rigidly mounted in the valve housing, extends thru a hole. in the stop, of slightly greater diameter than the pin, and a spring 79 presses the stop inwardly to its normal position against the pin. In case the compressor becomes filled with liquid sulphur dioxide or lubricating oil, a straining of the valves by the discharge of the liquid therethru, is prevented by the increased movement of the valve permitted by movement of the stop against its spring.

, The compressed gas escapes from the valve housings 72, directly into the chamber 6, thru ports 80, except from the lower valve housing, in which a tube 81 extends from the port and terminates well above the center of the chamber, as shown in Fig. 8. A

gauge 82 records the pressure of the gas in the receiver, and the suction pressure is shown on a gauge'83 in communication with the inlet passage 31.

The head of a piston at the completion of the compression stroke is substantially coincident with the lower face of the valve, just enough space being provided between them to eliminate pounding. The valve action is certain under all conditions. the valve being opened by the compressed gas in the cylinder and seated by a back pressure which is but slightly less than that developed in the cylinder. This certain action combined with an extremely small movement. allows the high speed valve action necessary for a compressor directly coupled to an electric motor.

A positive and continuous lubrication is necessary in a compressor operating at the speed contemplated for my device. discharge chamber 6contains a quantity of lubricating oil 84, partly submerging the compressor, the try cocks 85, indicating,

maximum and minimum oil levels in the chamber, which are below the end of the tube 81. From'the' above it will be clear that the oil is at all timesunderthe dis- The perature ranging from 90 F. to120 F its viscosity between these temperatures varying but slightly. The size of the oil holes and grooves in the compressor. giving the most efficient and economical lubrication, has been worked out, with the averageviscosity of lubricating oil between these temperatures, asa basis.

The cover plate 26 is provided with a bearing 87 adapted to receive one end of the drive shaft 38. The outer end of the bearing is tapped to receive an elbow 88 in which is screwed a short length of pipe 89, extending below the surface of the 021. A wick 91 is attached to the inside of the pipe 89 to prevent the oil from entering too rapidly and to strain out any particles of foreign matter. The oil on passing the elbow provides lubrication for the bearing 87 and enters the dnli-veshaft thru a central passage 92 extending to a point midway between the two vertical faces of the eccentric 39. A smaller passage 93 in communication with and at right angles to the passage 92, extends thru the eccentric to its highest point providing means for lubricating the eccentric and the interior circular face of the eccentric block. Oil passages 94, having an angular separation of 90. ex-

tend 'thru the eccentric-block and communicate with oil grooves 96 in the outer or peripheral faces which are in frictional engagement with the piston rods. thus providing lubrication for the piston rods 43 and 54 engaging thcse faces. At the compiston. the oil passage 93. Fig. 3. in the eccentric becomes almcd with an 011 passage 94 in the eccentric block. and these two with extendingbelow the surface of the oil. Es-

tablishingcommunication between the drive shaft and the inlet passage 31, Fig. 7. is a slot 101 in a gasket 102. interposed between the base plate 24 and the head 3. As the gas in the inlet passage is.-in normal operation of the refrigerating device, under substantially zero or atmospheric pressure. and

oil in the passage 98 is under the discharge pressure, an oil pressure, equivalent to the pletion of the compression stroke of each one end of the spring.

diflerence between the suction pressure and discharge pressure, is established in the hearing of the drive shaft. This lubrication of the bearing 97 provides anoil seal for the stufiing box 103, which comprises a gland 104 held against the packing by a spring 106, the tension of which is controlled by the nuts 107 thru the late 108, which bears on The compressor shown in the drawings has a stroke of' -inch and a bore of -inch. As each piston completes one full suction and discharge stroke in one revolution of the drive shaft, the piston travel for one revolution of the shaft is 2 inches. As the shaft is turning over at the rate of about 1750 revolutions er minute, the piston travel in that period is 3500 inches. Previous types of compressors with the same stroke and bore would have a very much lower capacity. For purposes of comparison, consider a two cylinder compressor of -inch stroke and bore and of the type usually incorporated in small refrigerating machines. The piston travel, per revolution of theshaft, is 1 inch;

At 350 revolutions per minute, the piston travel is 350 inches, or one-tenth of the piston travel in the preferred form of the compressor shown, indicating but one-tenth of the ca acity. In my compressor apparatus,

the friction losses have been found to be.

about 19%, under ordinary operating conditions. Other losses bring the total up to 31%, the machine having a theoretical rating of about 108 pounds and an actual rating of about 75:pounds, one pound of refrigeration being equivalent to the absorption of 144 B. t. u.s per 24 hours. The rating varies with the suction pressure, and at a suction pressureof 0 pounds and a dis- I charge pressure of'40 pounds, is about 75 1 pounds, while with a suction pressure of one pound and a discharge pressure of 40 pounds, the rating is increased about 20%.

The invention in its preferred form comprises a tour-cylinder compressor, as shown diagrammatically in Figs. 9 and 10, but modifications of the same type will give double and quadruple the capacity of the preferred form without increasing the ex- 1 ternal dimensions of the compressor, the easing enclosing the discharge chamber having been designed to accommodate such modifications.

Using the same cylinder block, an eightcylinder compressor may be made by forming, in each side of the cylinder block, a pair of cylinders 113 and 114, as shown in Figs. 11 and 12, cach pair of pistons'lltl and 11? o 'ierating as a unit.

Another eight-cylinder .modification, as shown in Fig. 13, is the combination of twocylinder blocks 118 and 119, of the type shown in Fig. 9, the eccentrics for operating ceiver for the compresse the four pistons in each block being set 180 a art.

A combination of two cylinder blocks of the eight-cylinder type, as'shown in Figs. 11 and 12, makes a sixteen-cylinder compressor, as shown in Fi 14.

Another mo ification giving eight cylinders is obtained by making the cylinder block 121, Fig. 16, to accommodate two cylinders 122 and 123 in each side thereof, the axis of the cylinders lying in vertical and horizontal planes passing thru the axis of the drive shaft, as shown in Figs. 15, 16

and 17. a

A combination of two cylinder blocks 121, Fig. 18, makes another modified form having 16 cylinders. Four eccentrics are required on the drive shaft.

lVe claim:

1.. In a compressor, a housing enclosing a supply chamber and formed with bores compassages extending from below the 2. The combination with a fluid compresbearings of a refluid and adapted to hold a quantity of oil, and passages extending from'below the oil level to said bearin s.

3. T e combination with a fluid compressor mechanism including a drive shaft, of a receiver for the compressed fluid and adapted to hold a quantity of oil,a passage extending from below the oil level to one side of said shaft, and a passage extending from the other side of said'shaft to the intake of said compressor.

4. In a compressor, a housing comprising a square ring and enclosing a supply cham-' her and formed with cylinder bores extend-- ing entirely thru the sides of the ring, pistons arranged in said cylinders, means for reciprocating said pistons, means for introducing the gas to be compressed into said chamber, passages from said chamber and opening into each cylinder adjacent its inncr end so as to be uncovered at the end ofthe suction stroke of the piston therein, and v a plate valve comprising an unattached disk overlying the opposite open end of each cylinder.

5. In a compressor, a housing enclosin a supply chamber and formed with cylinder sor mechanism including1 bores extending entirely therethru, pistons arranged in said cylinders, means for reciprocating said pistons, means for introducing the gas to be compressed into said chamber, means for establishing communication between one end of each cylinder and said chamber prior to the beginning of the compression stroke of the piston therein, a plate valve overlying the opposite open end of each cylinder, and a spring-pressed stop for limiting the movement of said plate valve.

6. In a compressor, a hollow block enclosing a supply chamber and formed with radially disposed bores in the peripheral Walls thereof comprising cylinders, pistons arranged in said 0 linders, a shaft, an eccentric disk on sai shaft in said chamber, a square block in which said disk is rotatable, a pair of bars connecting radially o posite pistons and in which said block is s idably arranged, said bars lying on opposite sides of said block, means for introducing the gas to be compressed into said chamber, means for opening communication between each cylinder and said chamber prior to the beginning of the compression stroke of the piston therein, and means for permitting the escape of the compressed gas from the cylinder.

7. In a compressor, a hollow block enclosing a supply chamber and formed with radially disposed bores in the peripheral walls thereo comprising cylinders, pistons arranged in said cylinders, a shaft an eccentric disk on said shaft in said chamber, a block in which said disk is rotatable, bars connecting radiall opposite pistons and in which said bloc is slida-bly arranged, means for introducing the gas to be compressed into said chamber, means for opening communication between each cylinder and said chamber prior to the beginning of the compression stroke of the piston therein, means for permitting the escape of the compressed gas from the cylinder, a receiver for said compressed gas enclosing said housing and adapted to hold a quantity of oil, and passages extending from below the oil level to said shaft, disk, block and pistons.

8. In a compressor apparatus, a receiver adapted to'hold a quantity of oil, a cover plate for closing one end of said receiver, a ousing enclosing a suppl chamber mounted on the inside of em cover plate and formed withbores comprising cylinders,

pistons in said cylinders, a shaft extending from said chamber to the outside of said receiver, means for operatively connecting said shaft to said pistons valves for permitting said pistons to draw fluid from said supply chamber and dischar e it into said receiver, and passages extending from one side of said shaft to below the oil level and from the other side of said shaft to said chamber.

9.. In'a compressor, a cylinder having a valve seat at the end thereof coextensive with the bore of the cylinder, a valve comprising an unattached disk arranged on said seat, and spring-pressed means for limiting the opening movement of said disk.

10. In a compressor, a cylinder having a valve seat at the end thereof coextensive with the bore of the cylinder, a valve comprising an unattached disk arranged on said seat, a stop having a rounded head disposed adjacent said disk, means for permitting limited movement of said stop, and a spring for retaining said stop in position closest to said disk.

11. In a compressor apparatus, a receiver adapted to hold a quantity .of oil, an enclosed compressor seated therein and discharging into said receiver, oil grooves in the operating mechanism of said compressor which become alined with each piston at the completion of its compressive stroke and establish communication between the piston and the oil insaid receiver.

12. In a compressor, a casing, a hollow block within said casing and enclosing a supply chamber, said hollow block being formed with a plurality of pairs of alined bores extending through its walls and comprising cylinders, pistons arranged in said cylinders and rigidly connected in pairs, means for reciprocating said pistons, means for introducing fluid to be compressed into said supply chamber, a port connecting each cylinder with the supply chamber and adapted to be uncovered by the piston prior to the beginning of the compression stroke, and means for permitting the escape of the compressed fluid from the outer and open ends of the cylinders to the interior of the casing.

In testimony whereof, we have hereunto set our hands.

HENRY C. MARCUS.

FRED FUURNESS, 

